Cd对桐花树幼苗生长及某些生理特性的影响

Effect of Cd on growth and physiological characteristics of Aegiceras conrniculatum seedlings

通过砂培实验研究了红树植物桐花树幼苗在含Cd0.05～100μg/L系列海水培养液(盐度为10)中的生长及某些生理特性的变化。当培养液中Cd浓度低于0.5μg/L时,随Cd浓度的增加,桐花树幼苗的生长加快,叶片叶绿素含量、过氧化物酶(POD)和超氧化物酶(SOD)活性均有所提高,而抽条水势则略有下降。而当高于0.5μg/L时,桐花树幼苗的生长减缓,叶片叶绿素含量、过氧化物酶(POD)和超氧化物酶(SOD)活性均出现不同程度的下降,抽条水势则迅速升高。不同Cd浓度下,桐花树叶片的细胞膜透性变化不大,但膜脂过氧化作用随着Cd浓度的增加而不断增强。红树植物桐花树对Cd金属有较强的耐性。

Based on the pots experiments in sand culture, the effect of heavy metal Cd on growth and some physiological characteristics of Aegiceras corniculatum mangrove seedlings were studied when treated by saline water with different concentrations of Cd (0.05～100μg/L). As Cd concentration increased from 0 to 0.5μg/L, the growth of Aegiceras corniculatum seedling was promoted, leaf chlorophyll content and activities of POD and SOD gradually increased. However, water potential of spouting branch had a little drop. When Cd concentration was higher than 0.5μg/L, the growth of Aegiceras corniculatum seedling was inhibited, leaf chlorophyll content and activities of POD and SOD began to decrease. but water potential of spouting branch took a significant rise. Under different Cd concentrations (0.05～100μg/L) in culture solution, cell membrane permeability had little change, but membrane lipid peroxidation gradually increased with the increase of Cd concentration. Aegiceras corniculatum mangrove plant had high toleration to heavy metal Cd.